1. Field of the Invention
The invention concerns a device and a method for controlling the commencement of operation of at least one tool in a fish processing machine in which tool and fish are moved relative to each other along a given conveying path, wherein the position of the fish in relation to the tool is determined by means of a guide element which penetrates into the interior of the fish, and after alignment of the fish as a result of penetration of this guide element the tool begins its application to or intervention in the fish.
2. Description of Related Art
In the processing or treatment of fish it is necessary in many cases, particularly when the fish is not yet gutted, that is, the abdominal cavity is not yet cleaned, to align it in the region thereof in order to open it by means of a slitting blade and then extract the entrails by means of a suction device and/or carry out cleaning in this region by means of scrapers, brushes or the like. In a traditional procedure such as is described e.g. in DE 198 29 376 A1, the fish is transported lying on its back in V-blocks of a chain conveyor, but machines in which it is guided and transported from the outside by means of conveyor belts are known too. In order to align it in relation to its central axis, a guide element is introduced into the abdominal cavity or digestive tract, which in the case of the prior-art device described is effected by means of a spike which penetrates into the anus.
With the known procedures, due to the fact that the fish is guided only relatively loosely in the holding V-blocks of the chain conveyor or between conveyor belts and for example fish deformation cannot be compensated, difficulties arise if the anus or other region of penetration is missed by such a spike. As a result of this, the spike pushes the fish sideways and then the point of the spike damages the scales covering the fish in the flank region. However, in particular subsequent tools such as suction devices, scrapers and above all even the slitting knife which here operates in a functional unit with the spike but can also be used separately, which tools are shown e.g. in DE 198 29 376 A1, destroy the fish at unwanted locations, thus especially the top side of the fish, so that the end product no longer meets the demanded premium quality requirements. This is a drawback particularly if, as described there, the aim is to make the so-called “princess cut”, which up to now could be made manually only, by machine (to which cut a gutting method refers which ensures a work result which meets the highest quality requirements and leaves the last 2 to 3 cm of the ventral wall in the gill region closed), and if it is wished above all to make noble or high-value fish accessible to machine processing as well.